Blackboard-eraser



(No Model.) v

D. L. CROFT.

BLAGKBOARD ERASER.

No. 274,566. Patented Mar.27,1883.

PATENT OFFICE.

DAVID L. CROFT, OF SPRINGFIELD, OHIO.

BLACKBOARD-ERASER.

SPECIFIGATION forming part of Letters Patent No. 274,566, dated March 27, 1883,

Application filed June 16, 1882. (No n odel.)

To all whom it may concern:

Be it known that I, DAVID L. ORoF'n, of Springfield, in the county of Clarke and State of Ohio, have invented certain Improvements in Blackboard-Erasers, of which the following is a specification.

M y invention relates to blackboard-erasers; and it consists in a novel manner of applying the facing or rubbing material to the block, whereby the cost is reduced and all tacks or other projecting fastenings are dispensed with.

In the accompanying drawings, Figure 1 represents a perspective view of my improved eraser; Fig. 2, a perspective view of the facingor rubbing material and its pasteboard form or filling; and Fig 3 is a vertical cross-section.

The object of my invention is to avoid the I use of tacks and at the same time permit the material to lie flat and even thereon.

facing material to project slightly past the edges of the biock, and to be used, in connection with a filling, the same as when tacked to the block. To this end ladopt the construction shown in the drawings, in which A represents the block or body to which the rubbing material Bis secured, the block being formed, as usual, with a rib, a, which aflbrds a convenient hold for the'hand. The rubbing material B, which is preferably corduroy, is laid upon a thin form, C, of pasteboard or like material, of a size corresponding closely to the face of the block A, the material being turned over upon theback of the form C and cut on t at the corners, so that the overturned portions form a series of miter-joints, thus causing the A suitable filling, D, of cotton-batting or other soft and elastic material, is interposed between the face of the thin form C and the rubbing material to give proper elasticity to the eraser, and

the overturned edges or flaps b are then glued, pasted, or cemented to the back of the form C, after which the form, with the covering applied and secured thereto, is glued or cementedto the face of block A, thereby completing the eraser. it will be seen that by this coustruction no projection of any kind is produced which might injure the surface of the board. The form 0, being of the same size as the block, causes the covering material B to project slight ly beyond the edge of the block all around,

and thus to prevent the block from coming into contact with the board.

1 am aware that felt has been secured to the face of a block or body by cement, and that various materials have been turned over the 5 edges of a block or wooden core and clamped between said core and a handle-piece or backing, the wooden core and backing being united by screws or a T-shaped tenon of one part sliding in to a corresponding groove in the other part, and 1 do not claim either of said constructions.

Having thus described my invention, what I claim isi. The herein-described eraser, consisting of 6 body A and rubbing material B, folded over the edges or a thin form, 0, and cemented thereto, and also cemented to the block.

2. The herein-described eraser, consisting of block A, rubbing material B, and thin form C, 7 the rubbing material being folded over the edges of the form, out out at the corners to lie flat thereon, and cemented to the form and to the block A, all as shown and described.

7 DAVID L. CRQFT.

Wi tnesses: H. S. Snownns, J. M. BENNETT. 

